In JoVE (1)

Other Publications (43)

Articles by Brian Gray in JoVE

Other articles by Brian Gray on PubMed

Highly Selective Entry to the Azadirachtin Skeleton Via a Claisen Rearrangement/radical Cyclization Sequence

Organic Letters. Oct, 2002  |  Pubmed ID: 12599474

[formula: see text] A highly diastereoselective, microwave-induced Claisen rearrangement of an appropriately substituted propargylic enol ether allows the formation of the sterically congested C8-C14 bond of azadirachtin. When combined with a radical-mediated cyclization of the corresponding allene, this sequence offers rapid entry to the framework of azadirachtin.

Concurrence of Fragile X Syndrome and 47, XYY in an Individual with a Prader-Willi-like Phenotype

American Journal of Medical Genetics. Part A. Jan, 2003  |  Pubmed ID: 12494438

We report on a 34-year-old developmentally disabled man referred to our clinic for evaluation of possible Prader-Willi syndrome on the basis of obesity and voracious appetite. Cytogenetic and molecular analysis revealed a 47, XYY karyotype and the presence of a trinucleotide repeat expansion resulting in fragile X syndrome. To our knowledge, this is the first report of concurrence of XYY and fragile X syndrome in the medical literature. Review of sex chromosome abnormalities associated with fragile X syndrome and phenotypic considerations are presented.

Routine Cytogenetic and FISH Studies for 17p11/15q11 Duplications and Subtelomeric Rearrangement Studies in Children with Autism Spectrum Disorders

American Journal of Medical Genetics. Part A. Mar, 2003  |  Pubmed ID: 12567405

To assess the frequency of cytogenetic abnormalities in children with autism spectrum disorders (ASDs), routine G-banded cytogenetic analyses and FISH studies to rule out 15q11.2 and 17p11.2 duplications were performed on 49 children with ASDs. Blood samples were further studied using a complete set of subtelomeric FISH probes. Routine chromosome study showed that one child had a small duplication of chromosome 5: 46,XY,dup(5)(p?14.2p?15.1). Another child had an interstitial duplication of the Prader-Willi and Angelman syndrome critical region of chromosome 15, detected by FISH analysis. The detection of these two cases underscores the importance of obtaining routine chromosome and 15q11-q13 FISH analyses in children with ASDs. No instance of 17p11.2 duplication was observed. Subtelomeric analysis did not reveal abnormalities in any of the subjects.

Translocation (X;20)(q13.1;q13.3) As a Primary Chromosomal Finding in Two Patients with Myelocytic Disorders

Cancer Genetics and Cytogenetics. Mar, 2003  |  Pubmed ID: 12606138

Reports of X chromosome translocations, as primary chromosomal changes associated with hematologic disorders, remain relatively uncommon. Herein, we report the detection, by conventional cytogenetic methods, of a cytogenetically identical t(X;20) in two different patients with hematologic disorders (probable myelodysplasia and polycythemia vera/acute myelocytic leukemia). In both cases, this translocation appeared as the primary clonal chromosome abnormality, with breakpoints occurring in the long arms of both the X chromosome and chromosome 20 (Xq13.1 and 20q13.3, respectively). Further characterization and comparison of the translocation chromosome products of these two cases by use of fluorescence in situ hybridization techniques is also described. Similar previously reported cytogenetically cases and the potential that this specific rearrangement may represent a nonrandom chromosomal finding are discussed.

Report Questioned

Journal of the American Dental Association (1939). Mar, 2003  |  Pubmed ID: 12699040

Repair of Giant Abdominal Hernias: Does the Type of Prosthesis Matter?

The American Surgeon. May, 2004  |  Pubmed ID: 15156946

Closure of the abdominal wall after trauma or major surgery may be difficult due to visceral edema or fascial weakness; thus, the risk of developing a ventral hernia (VH) is high. Commonly, these hernias are repaired using a prosthetic mesh. Complications following mesh repair can develop. We hypothesize that the type of prosthetic material affects outcome. This is a retrospective chart review of patients admitted from 1996 to 2002 undergoing VH (> or = 20 x 10 cm) repair with prosthetic mesh. Data collected included age, sex, and race. Patients were stratified by prosthetic material as follows: Gore-Tex (GR), Marlex + Gore-Tex (MG), Marlex (MR), and Marlex + Vicryl (MV). For the purpose of clinical analysis, the groups were collapsed into subgroups: Gore-Tex exposure (GT) or non-Gore-Tex exposure (NG). Outcome measures were hernia recurrence (HR), wound infection (WI), and fistula formation (FF). Statistical analysis utilized chi2 test and Fisher's exact test. There were 55 VH repairs in 37 patients. The mean age was 43.9 (+/- 16.3), males out-numbered females 22 (59.5%) to 15 (40.5%). The majority of the patients were Caucasian (29; 78.4%). There were 30 trauma patients (81.1%), and 7 general surgery patients (18.9%). The HR for the study (n = 55) was 20 (36.4%), the WI was 17 (30.9%), and the FF was 3 (5.5%). GR group (6; 66.7%) had a significant higher wound IF rate than MR group (8; 26.7%) (Chi P = 0.02, Fisher P = 0.047). All other group comparisons (HR, WI, and FF) were N.S. The Gore-Tex versus non-Gore-Tex subgroup comparison results were as follows: GT (n = 18) had a WI 8 (44.4%), HR 6 (33.3%), and FF 0 (0%). NG (n = 37) had a WI 9 (24.3%), HR 14 (37.8%), and a FF 3 (8.1%). There was a trend toward a higher wound infection in the GT versus NG, but it did not reach statistical significance. We conclude that 1) the wound infection rate was higher in the Gore-Tex versus the Marlex group (Chi P = 0.02, Fisher P = 0.047). Wound infection in the presence of Gore-Tex usually mandates the removal of the mesh resulting in a hernia recurrence. 2) There was a trend toward a higher wound infection in the GT (44.4%) versus NG (24.3%), but it did not reach statistical significance.

Trace Elements in Moose (Alces Alces) Found Dead in Northwestern Minnesota, USA

The Science of the Total Environment. Sep, 2004  |  Pubmed ID: 15325160

The moose (Alces alces) population in bog and forest areas of Northwestern Minnesota has declined for more than 25 years, and more recently the decline is throughout Northwestern Minnesota. Both deficiencies and elevations in trace elements have been linked to the health of moose worldwide. The objective of this study was to evaluate whether trace element toxicity or deficiency may have contributed to the decline of moose in Northwestern Minnesota. Livers of 81 moose found dead in Northwestern Minnesota in 1998 and 1999 were analyzed for trace elements. With the exception of selenium (Se) and copper (Cu), trace elements were not at toxic or deficient levels based on criteria set for cattle. Selenium concentrations in moose livers based on criteria set for cattle were deficient in 3.7% of livers and at a chronic toxicity level in 16% of livers. Copper concentrations based on criteria set for cattle were deficient in 39.5% of livers, marginally deficient in 29.5% of livers and adequate in 31% of livers. Moose from agricultural areas had higher concentrations, on average, of Cd, Cu, Mo and Se in their livers than moose from bog and forest areas. Older moose had higher concentrations of Cd and Zn, and lower concentrations of Cu than younger moose. Copper deficiency, which has been associated with population declines of moose in Alaska and Sweden, may be a factor contributing to the decline of moose in Northwestern Minnesota.

MR and Fluorescent Imaging of Low-density Lipoprotein Receptors

Academic Radiology. Nov, 2004  |  Pubmed ID: 15561572

Over-expression of low-density lipoprotein receptors (LDLRs) occurs in many types of malignancies and is related to the requirement for lipids for rapid proliferation of the tumors. On the other hand, LDLRs that are unable to bind LDL are found on hepatocytes of patients with familial hypercholesterolemia (FH), a genetic disease that leads to premature atherosclerosis and death. The highly selective binding of LDL to LDLR makes these particles ideal carriers of therapeutic and diagnostic contrast agents into the targeted cells. The objectives of this paper are to examine whether a prototype contrast agent (PTIR267) with dual detection properties is suitable for labeling of LDL particles for in vivo detection of LDLR by magnetic resonance imaging (MRI) and for in vitro monitoring of cellular localization by confocal fluorescence microscopy.

Rapid Measurement and Evaluation of the Effect of Drying Conditions on Harpagoside Content in Harpagophytum Procumbens (devil's Claw) Root

Journal of Agricultural and Food Chemistry. May, 2005  |  Pubmed ID: 15853393

The effect of drying conditions on harpagoside (HS) retention, as well as the use of near-infrared spectroscopy (NIRS) for rapid quantification of the iridoids, HS, and 8-rho-coumaroyl harpagide (8rhoCHG) and moisture, in dried Harpagophytum procumbens (devil's claw) root was investigated. HS retention was significantly (P < 0.05) lower in sun-dried samples as compared to tunnel-dried (60 degrees C, 30% relative humidity) and freeze-dried samples. The best retention of HS was obtained at 50 degrees C when evaluating tunnel drying at dry bulb temperatures of 40, 50, and 60 degrees C and 30% relative humidity. NIRS can effectively predict moisture content with a standard error of prediction (SEP) and correlation coefficient (r) of 0.24% and 0.99, respectively. The HS and 8rhoCHG NIRS calibration models established for both iridoid glucosides can be used for screening purposes to get a semiquantitative classification of devil's claw roots (for HS: SEP = 0.236%, r = 0.64; for 8rhoCHG: SEP = 0.048%, r = 0.73).

Flow Cytometer in the Infrared: Inexpensive Modifications to a Commercial Instrument

Cytometry. Part A : the Journal of the International Society for Analytical Cytology. Oct, 2005  |  Pubmed ID: 16163692

The application of molecules that fluoresce in the infrared (IR) region to measure cell products would be enhanced by a flow cytometer capable of measuring them. To our knowledge, none exist at this time. Accordingly, we have developed such an instrument.

Diagnosis of an Early Precursor-B-ALL Presenting with Hypereosinophilia Using FISH on Immunomagnetically Selected CD19+ Cells

Clinical Advances in Hematology & Oncology : H&O. Jan, 2005  |  Pubmed ID: 16166969

G-banded Karyotype and Ideogram for the North Atlantic Right Whale (Eubalaena Glacialis)

The Journal of Heredity. May-Jun, 2006  |  Pubmed ID: 16598035

Published cytogenetic data for extant cetacean species remain incomplete. In a review of the literature, we found karyotypic information for 6 of the 13 tentatively recognized species of the suborder Mysticeti (baleen whales). Among those yet to be described is the critically endangered North Atlantic right whale (Eubalaena glacialis). Herein, we describe and propose a first-generation G-banded karyotype and ideogram for this species (2n = 42), obtained from peripheral blood chromosome preparations from a stranded male calf. This information may prove useful for future genetic mapping projects and for interspecific and intraspecific genomic comparisons by techniques such as zoo-FISH.

Role of Transcription Factor T-bet Expression by CD4+ Cells in Gastritis Due to Helicobacter Pylori in Mice

Infection and Immunity. Aug, 2006  |  Pubmed ID: 16861655

Gastritis due to Helicobacter pylori is induced by a Th1-mediated response that is CD4 cell and gamma interferon (IFN-gamma) dependent. T-bet is a transcription factor that directs differentiation of and IFN-gamma secretion by CD4+ Th1 T cells. The goal of this study was to use two mouse models to elucidate the role of T-bet in gastritis due to H. pylori. C57BL/6J mice, congenic T-bet knockout (KO) mutants, or congenic SCID (severe, combined immunodeficient) mutants were given live H. pylori by oral inoculation. SCID mice were given CD4+ splenocytes from C57BL/6J or T-bet KO mice by intraperitoneal injection. Twelve or 24 weeks after bacterial inoculation, C57BL/6J mice developed moderate gastritis but T-bet KO mice and SCID mice did not. In contrast, SCID recipients of either C57BL/6J T cells or T-bet KO T cells developed gastritis 4 or 8 weeks after adoptive transfer. In recipients of C57BL/6J CD4+ cells but not recipients of T-bet KO cells, gastritis was associated with a delayed-type hypersensitivity response to H. pylori antigen and elevated gastric and serum IFN-gamma, interleukin 6, and tumor necrosis factor alpha. In spite of the absence of IFN-gamma expression, indicating failure of Th1 differentiation, CD4+ T cells from T-bet KO mice induce gastritis in H. pylori-infected recipient SCID mice. This indicates that Th1-independent mechanisms can cause gastric inflammation and disease due to H. pylori.

Chromosome Painting in the Manatee Supports Afrotheria and Paenungulata

BMC Evolutionary Biology. 2007  |  Pubmed ID: 17244368

Sirenia (manatees, dugongs and Stellar's sea cow) have no evolutionary relationship with other marine mammals, despite similarities in adaptations and body shape. Recent phylogenomic results place Sirenia in Afrotheria and with elephants and rock hyraxes in Paenungulata. Sirenia and Hyracoidea are the two afrotherian orders as yet unstudied by comparative molecular cytogenetics. Here we report on the chromosome painting of the Florida manatee.

Effects of Methylmercury Exposure on the Immune Function of Juvenile Common Loons (Gavia Immer)

Environmental Toxicology and Chemistry / SETAC. Jul, 2007  |  Pubmed ID: 17665687

We conducted a dose-response laboratory study to quantify the level of exposure to dietary Hg, delivered as methylmercury chloride (CH3HgCl), that is associated with suppressed immune function in captive-reared common loon (Gavia immer) chicks. We used the phytohemagglutinin (PHA) skin test to assess T-lymphocyte function and the sheep red blood cell (SRBC) hemagglutination test to measure antibody-mediated immunity. The PHA stimulation index among chicks receiving dietary Hg treatment did not differ significantly from those of chicks on the control diet (p = 0.15). Total antibody (immunoglobulin [Ig] M [primary antibody] + IgG [secondary response]) production to the SRBC antigen in chicks treated with dietary methylmercury (MeHg), however, was suppressed (p = 0.04) relative to chicks on control diets. Analysis indicated suppression of total Ig production (p = 0.025 with comparisonwise alpha level = 0.017) between control and 0.4 microg Hg/g wet food intake treatment groups. Furthermore, the control group exhibited a higher degree of variability in antibody response compared to the Hg groups, suggesting that in addition to reducing the mean response, Hg treatment reduced the normal variation attributable to other biological factors. We observed bursal lymphoid depletion in chicks receiving the 1.2 microg Hg/g treatment (p = 0.017) and a marginally significant effect (p = 0.025) in chicks receiving the 0.4 microg Hg/g diet. These findings suggest that common loon chick immune systems may be compromised at an ecologically relevant dietary exposure concentration (0.4 microg Hg/g wet wt food intake). We also found that chicks hatched from eggs collected from low-pH lakes exhibited higher levels of lymphoid depletion in bursa tissue relative to chicks hatched from eggs collected from neutral-pH lakes.

Estimating Trend Precision and Power to Detect Trends Across Grouped Count Data

Ecology. Sep, 2007  |  Pubmed ID: 17918413

Ecologists commonly use grouped or clustered count data to estimate temporal trends in counts, abundance indices, or abundance. For example, the U.S. Breeding Bird Survey data represent multiple counts of birds from within each of multiple, spatially defined routes. Despite a reliance on grouped counts, analytical methods for prospectively estimating precision of trend estimates or statistical power to detect trends that explicitly acknowledge the characteristics of grouped count data are undescribed. These characteristics include the fact that the sampling variance is an increasing function of the mean, and that sampling and group-level variance estimates are generally estimated on different scales (the sampling and log scales, respectively). We address these issues for repeated sampling of a single population using an analytical approach that has the flavor of a generalized linear mixed model, specifically that of a negative binomial-distributed count variable with random group effects. The count mean, including grand intercept, trend, and random group effects, is modeled linearly on the log scale, while sampling variance of the mean is estimated on the log scale via the delta method. Results compared favorably with those derived using Monte Carlo simulations. For example, at trend = 5% per temporal unit, differences in standard errors and in power were modest relative to those estimated by simulation (< or = /11/% and < or = /16/%, respectively), with relative differences among power estimates decreasing to < or = /7/% when power estimated by simulations was > or = 0.50. Similar findings were obtained using data from nine surveys of fingernail clams in the Mississippi River. The proposed method is suggested (1) where simulations are not practical and relative precision or power is desired, or (2) when multiple precision or power calculations are required and where the accuracy of a fraction of those calculations will be confirmed using simulations.

CellVue Claret, a New Far-red Dye, Facilitates Polychromatic Assessment of Immune Cell Proliferation

Immunological Investigations. 2007  |  Pubmed ID: 18161520

Flow cytometric analyses of immune cell proliferation, differentiation, and function are limited by the number of different fluorochromes that can be resolved simultaneously. Additional colors to expand functional analytic capability will facilitate higher dimensional analyses of heterogeneous cell populations by basic and clinical scientists. Our aim in these studies was to evaluate CellVue Claret, a fluorescent, far-red emitting, membrane intercalating dye (excitation maximum: 655 nm, emission maximum 677 nm), as an alternative and/or complementary probe to PKH26 and CFSE(1) for polychromatic studies of immune cell proliferation and function. Using a BD FACSCalibur and human peripheral blood mononuclear cells (PBMCs) from 8 different donors (2 donors studied twice), we compared CellVue Claret with the two most commonly used visible-emitting proliferation dyes, PKH26 and CFSE, in terms of: (1) compatibility with 7-Amino-actinomycin D (7-AAD) as a viability marker; (2) effect of dye labeling on lymphocyte viability; and (3) the proliferative response of CD3+ T lymphocytes from 0-96 hours as assessed by dilution of each of the 3 cell tracking dyes in cultures stimulated with anti-CD3 plus IL-2. Post-labeling recoveries and viabilities were similar for all 3 dyes, with modestly higher initial staining intensities and coefficients of variation for CellVue Claret than for CFSE or PKH26. Lymphocyte viabilities in stimulated or unstimulated cultures were also unaffected by choice of dye. Proliferative responses of viable CD3+ lymphocytes were comparable for all three dyes, whether results were reported as Proliferative Fraction (percent of cells that had divided one or more times) or as Precursor Frequency (percent of parent population that had gone on to proliferate in response to anti-CD3 plus IL-2). In summary, T cell proliferation analysis using CellVue Claret gives results equivalent to those obtained with PKH26 or CFSE, expanding the choice of proliferation dyes suitable for use in high dimensional polychromatic studies on flow cytometers with far red (633 nm-658 nm) excitation capabilities.

Lipophilic Fluorochrome Trackers of Membrane Transfers Between Immune Cells

Immunological Investigations. 2007  |  Pubmed ID: 18161524

Cell-to-cell transfers of membrane molecules between lymphoid cells (sometimes referred to as trogocytosis) is frequent and has multiple physiological consequences. Although difficult to visualize through the tracking of defined cell surface proteins, this process can be readily monitored by inserting PKH or CellVue Maroon fluorochromes into the plasma membranes of donor cells. We discuss here parameters that determine its detection by a flow-cytometry-based in vitro assay and present examples of application, including time-lapse video-microscopy analysis of transfers at the immunological synapse. By combining detection of cell-to-cell transfer and of cell surface CD107, it is possible to discriminate lymphoid cells binding target cells with and without perforin release. This could prove useful for identifying cells that destruct known target cells in autoimmune pathologies.

Long-distance Three-color Neuronal Tracing in Fixed Tissue Using NeuroVue Dyes

Immunological Investigations. 2007  |  Pubmed ID: 18161528

Dissecting development of neuronal connections is critical for understanding neuronal function in both normal and diseased states. Charting the development of the multitude of connections is a monumental task, since a given neuron typically receives hundreds of convergent inputs from other neurons and provides divergent outputs for hundreds of other neurons. Although progress is being made utilizing various mutants and/or genetic constructs expressing fluorescent proteins like GFP, substantial work remains before a database documenting the development and final location of the neuronal pathways in an adult animal is completed. The vast majority of developing neurons cannot be specifically labeled with antibodies and making specific GFP-expressing constructs to tag each of them is an overwhelming task. Fortunately, fluorescent lipophilic dyes have emerged as very useful tools to systematically compare changes in neuronal networks between wild-type and mutant mice. These dyes diffuse laterally along nerve cell membranes in fixed preparations, allowing tracing of the position of a given neuron within the neuronal network in murine mutants fixed at various stages of development. Until recently, however, most evaluations have been limited to one, or at most, two color analyses. We have previously reported three color neuronal profiling using the novel lipophilic dyes NeuroVue (NV) Green, Red and Maroon (Fritzsch et al., Brain. Res. Bull. 66: 249-258, 2005). Unfortunately such three color experiments have been limited by the fact that NV Green and its brighter successor, NV Emerald, both exhibit substantially decreased signal intensities when times greater than 48 hours at 37 degrees C are required to achieve neuronal profile filling (unpublished observations). Here we describe a standardized test system developed to allow comparison of candidate dyes and its use to evaluate a series of 488 nm-excited green-emitting lipophilic dyes. The best of these, NV Jade, has spectral properties well matched to NV Red and NV Maroon, better solubility in DMF than DiO or DiA, improved thermostability compared with NV Emerald, and the ability to fill neuronal profiles at rates of 1 mm per day for periods of at least 5 days. Use of NV Jade in combination with NV Red and NV Maroon substantially improves the efficiency of connectional analysis in complex mutants and transgenic models where limited numbers of specimens are available.

Novel Lipophilic Tracking Dyes for Monitoring Cell Proliferation

Immunological Investigations. 2007  |  Pubmed ID: 18161533

The advent of contemporary digital instrumentation has enhanced both the potential and the complexity of flow cytometric experiments, allowing for the detailed dissection of immune cell subsets and their functions. The use of cell tracking labels such as PKH26 and CFSE has been important in observing such cellular functions, but their visible emission characteristics have limited the design of such analyses. As the demand for multiparametric flow cytometry intensifies, it will become increasingly important to utilize a broader range of cell tracking reagents to optimize the measurement of fluorescence signals and to provide flexibility in the use of commercially available fluorochrome - antibody combinations. We report on the evaluation of three lipophilic membrane dyes, CellVue Lavender, CellVue Plum and CellVue NIR780; with fluorescence emissions in the violet, far-red and near infrared wavelength regions, respectively. These reagents are similar to established tracking dyes such as PKH26 and CFSE in terms of staining procedure, membrane stability, optimal concentration, and lack of effect on cellular proliferation. The CellVue dyes however, exhibit different spectral characteristics than existing tracking compounds, and capitalize upon the increased number of lasers incorporated into commercially available instrumentation; thus permitting measurement of labeled populations in underexploited regions of the spectrum.

Intracranial Myeloid Sarcoma

British Journal of Haematology. Sep, 2008  |  Pubmed ID: 18477037

The Synthesis of Azadirachtin: a Potent Insect Antifeedant

Chemistry (Weinheim an Der Bergstrasse, Germany). 2008  |  Pubmed ID: 18821532

We describe in full the first synthesis of the potent insect antifeedant azadirachtin through a highly convergent approach. An O-alkylation reaction is used to unite decalin ketone and propargylic mesylate fragments, after which a Claisen rearrangement constructs the central C8-C14 bond in a stereoselective fashion. The allene which results from this sequence then enables a second critical carbon-carbon bond forming event whereby the [3.2.1] bicyclic system, present in the natural product, is generated via a 5-exo-radical cyclisation process. Finally, using knowledge gained through our early studies into the reactivity of the natural product, a series of carefully designed steps completes the synthesis of this challenging molecule.

Aldehyde Dehydrogenase Activity As a Functional Marker for Lung Cancer

Chemico-biological Interactions. Mar, 2009  |  Pubmed ID: 18952074

Aldehyde dehydrogenase (ALDH) activity has been implicated in multiple biological and biochemical pathways and has been used to identify potential cancer stem cells. Our main hypothesis is that ALDH activity may be a lung cancer stem cell marker. Using flow cytometry, we sorted cells with bright (ALDH(br)) and dim (ALDH(lo)) ALDH activity found in H522 lung cancer cell line. We used in vitro proliferation and colony assays as well as a xenograft animal model to test our hypothesis. Cytogenetic analysis demonstrated that the ALDH(br) cells are indeed a different clone, but when left in normal culture conditions will give rise to ALDH(lo) cells. Furthermore, the ALDH(br) cells grow slower, have low clonal efficiency, and give rise to morphologically distinct colonies. The ability to form primary xenografts in NOD/SCID mice by ALDH(br) and ALDH(lo) cells was tested by injecting single cell suspension under the skin in each flank of same animal. Tumor size was calculated weekly. ALDH1A1 and ALDH3A1 immunohistochemistry (IHC) was performed on excised tumors. These tumors were also used to re-establish cell suspension, measure ALDH activity, and re-injection for secondary and tertiary transplants. The results indicate that both cell types can form tumors but the ones from ALDH(br) cells grew much slower in primary recipient mice. Histologically, there was no significant difference in the expression of ALDH in primary tumors originating from ALDH(br) or ALDH(lo) cells. Secondary and tertiary xenografts originating from ALDH(br) grew faster and bigger than those formed by ALDH(lo) cells. In conclusion, ALDH(br) cells may have some of the traditional features of stem cells in terms of being mostly dormant and slow to divide, but require support of other cells (ALDH(lo)) to sustain tumor growth. These observations and the known role of ALDH in drug resistance may have significant therapeutic implications in the treatment of lung cancer.

Associations Between Land Use and Perkinsus Marinus Infection of Eastern Oysters in a High Salinity, Partially Urbanized Estuary

Ecotoxicology (London, England). Feb, 2009  |  Pubmed ID: 19015979

Infection levels of eastern oysters by the unicellular pathogen Perkinsus marinus have been associated with anthropogenic influences in laboratory studies. However, these relationships have been difficult to investigate in the field because anthropogenic inputs are often associated with natural influences such as freshwater inflow, which can also affect infection levels. We addressed P. marinus-land use associations using field-collected data from Murrells Inlet, South Carolina, USA, a developed, coastal estuary with relatively minor freshwater inputs. Ten oysters from each of 30 reefs were sampled quarterly in each of 2 years. Distances to nearest urbanized land class and to nearest stormwater outfall were measured via both tidal creeks and an elaboration of Euclidean distance. As the forms of any associations between oyster infection and distance to urbanization were unknown a priori, we used data from the first and second years of the study as exploratory and confirmatory datasets, respectively. With one exception, quarterly land use associations identified using the exploratory dataset were not confirmed using the confirmatory dataset. The exception was an association between the prevalence of moderate to high infection levels in winter and decreasing distance to nearest urban land use. Given that the study design appeared adequate to detect effects inferred from the exploratory dataset, these results suggest that effects of land use gradients were largely insubstantial or were ephemeral with duration less than 3 months.

Long-term Disease Control of Refractory Anaplastic Large Cell Lymphoma with Vinblastine

Journal of Pediatric Hematology/oncology. Feb, 2009  |  Pubmed ID: 19194204

Anaplastic large cell lymphoma (ALCL) is a unique clinical and pathologic subtype of lymphoma characterized by the proliferation of large, highly pleomorphic CD30-positive cells. Overall 70% to 80% of children with ALCL are cured with modern chemotherapy regimens, but the disease is often resistant to multiple therapies after relapse. Single agent vinblastine therapy has been effective in some cases of refractory ALCL. We report a case of ALCL originally diagnosed in an 8-year-old girl. After relapse, the disease was refractory to multiagent chemotherapy, but has showed remarkable response to, and dependence on, single agent vinblastine treatment for almost 7 years.

Imaging Membrane Intercalating Near Infrared Dyes to Track Multiple Cell Populations

Journal of Immunological Methods. Aug, 2009  |  Pubmed ID: 19559026

Given the increasing interest in understanding in vivo migration of different cell types, it would be useful to have a simple method for tracking multiple cell populations in animals. Here we evaluated near infrared (NIR) dyes that intercalate into cell membranes as cell tracking labels, using both high-throughput and high-resolution methods. We tracked cells in tissues containing significant autofluorescence. CellVue Burgundy (ex 683/em 707) and CellVue NIR815 (ex 786/em 814) are especially useful because their spectral properties match the laser and detectors of the LI-COR laser scanner. After labeling cells ex vivo and injecting them into tumor-bearing mice, the distribution of cells in tumor and organs could be quantified in tissue sections with high throughput by scanning many slides at once. For example, we compared brain tumor infiltration and organ distribution of naïve and activated lymphocytes in single animals. High-resolution microscopic examination of the same tissues could be done by a relatively inexpensive modification of an epifluorescence microscope using a custom designed diode laser light source. Light emitting diodes that emit 685 nm and 780 nm light allowed microscopic visualization of the NIR labeled cells in tissues. The NIR dye-labeled cells were visualized with a greater signal/noise ratio compared to visible wavelength dyes such as CFSE, because of the low levels of autofluorescence in the NIR range. We also describe a simple modification of immunohistochemical procedures that allows combined visualization of the hydrophobic NIR dyes and antibody probes of cell markers in unfixed tissue. In combination these techniques will facilitate cell tracking in vivo.

Polychlorinated Biphenyls, Dioxins, Furans, and Organochlorine Pesticides in Spotted Sandpiper Eggs from the Upper Hudson River Basin, New York

Ecotoxicology (London, England). Feb, 2010  |  Pubmed ID: 19809875

In 2004, spotted sandpipers (Actitis macularia) were studied on the Hudson River near Fort Edward south to New Baltimore, NY and on two river drainages that flow into the Hudson River. Concentrations of 28 organochlorine pesticides, 160 polychlorinated biphenyl (PCB) congeners, and 17 dioxin and furan (PCDD-F) congeners were quantified in eggs collected on and off the Hudson River. The pattern of organochlorine pesticides and PCDD-F congeners did not differ significantly between eggs collected on and off the Hudson River. In contrast, the pattern of PCB congeners differed significantly between the Hudson River and other rivers. Total PCBs were significantly greater in eggs from the Hudson River (geometric mean = 9.1 microg PCBs/g wet weight) than from the other two rivers (0.6 and 0.6 microg PCBs/g wet weight). Seven of 35 (20%) eggs exceeded 20 microg PCBs/g wet weight, the estimated threshold for reduced hatching in tree swallows (Tachycineta bicolor) and some raptor species; the maximum concentration was 72.3 microg PCBs/g wet weight. Models that predicted nest survival and egg success (the proportion of eggs hatching in a clutch if at least one egg hatched) as functions of contaminant levels were poorly distinguished from models that presumed no such associations. While small sample size could have contributed to the inability to distinguish among contaminant and no toxicant models, we cannot rule out the possibility that contaminant concentrations on the Hudson River were not sufficiently high to demonstrate a relationship between contaminant concentrations and reproductive success.

Effect of Imperfect Detectability on Adaptive and Conventional Sampling: Simulated Sampling of Freshwater Mussels in the Upper Mississippi River

Environmental Monitoring and Assessment. Nov, 2010  |  Pubmed ID: 19946742

Adaptive sampling designs are recommended where, as is typical with freshwater mussels, the outcome of interest is rare and clustered. However, the performance of adaptive designs has not been investigated when outcomes are not only rare and clustered but also imperfectly detected. We address this combination of challenges using data simulated to mimic properties of freshwater mussels from a reach of the upper Mississippi River. Simulations were conducted under a range of sample sizes and detection probabilities. Under perfect detection, efficiency of the adaptive sampling design increased relative to the conventional design as sample size increased and as density decreased. Also, the probability of sampling occupied habitat was four times higher for adaptive than conventional sampling of the lowest density population examined. However, imperfect detection resulted in substantial biases in sample means and variances under both adaptive sampling and conventional designs. The efficiency of adaptive sampling declined with decreasing detectability. Also, the probability of encountering an occupied unit during adaptive sampling, relative to conventional sampling declined with decreasing detectability. Thus, the potential gains in the application of adaptive sampling to rare and clustered populations relative to conventional sampling are reduced when detection is imperfect. The results highlight the need to increase or estimate detection to improve performance of conventional and adaptive sampling designs.

Effects of Methylmercury Exposure on the Behavior of Captive-reared Common Loon (Gavia Immer) Chicks

Ecotoxicology (London, England). Jun, 2010  |  Pubmed ID: 20217222

Behavioral effects resulting from exposure to dietary methylmercury (MeHg) have been reported in studies of several wildlife species. However, quantifying the impact of contaminant exposure on wild populations is complicated by the confounding effects of other environmental stressors. We controlled confounding stressors in a laboratory study to quantify the level of dietary MeHg exposure associated with negative effects on the fitness of captive-reared common loon (Gavia immer) chicks. We evaluated the effect of MeHg on loon chick behavior by employing several assays, including measures of righting reflexes, responsiveness to taped parental calls, reaction to frightening stimuli, and estimates of time activity budgets. Evidence suggested that as chicks aged, those exposed to nominal dietary dose levels of 0.4 and 1.2 microg Hg/g wet-weight in food (average estimated delivered dietary level of 0.55 and 1.94 microg Hg/g, respectively) were less likely (p < 0.01) to right themselves after being positioned on their backs during outdoor trials (> or =37 days old) compared to chicks on the control diet. We detected differences (p < 0.05) in several response variables with respect to source of eggs. Chicks from nests on low-pH lakes tended to spend more time on resting platforms, spent less time in the shade, were more likely to walk across a platform upon release and do it quicker, were less responsive to a frightening stimulus, and exhibited less intense response to parental wail calls than did chicks from neutral pH-lakes. Rapid MeHg excretion during feather growth likely provides loon chicks protection from MeHg toxicity and may explain the lack of behavioral differences with dietary intake. Lake source effects suggest that in ovo exposure to MeHg or other factors related to lake pH have consequences on chick behavior.

Acoustic Experience Shapes Alternative Mating Tactics and Reproductive Investment in Male Field Crickets

Current Biology : CB. May, 2010  |  Pubmed ID: 20417103

Developmental plasticity allows juvenile animals to assess environmental cues and adaptively shape behavioral and morphological traits to maximize fitness in their adult environment. Sexual signals are particularly conspicuous cues, making them likely candidates for mediating such responses. Plasticity in male reproductive traits is a common phenomenon, but empirical evidence for signal-mediated plasticity in males is lacking. We tested whether experience of acoustic sexual signals during juvenile stages influences the development of three adult traits in the continuously breeding field cricket Teleogryllus oceanicus: male mating tactics, reproductive investment, and condition. All three traits were affected by juvenile acoustic experience. Males of this species produce a long-range calling song to attract receptive females, but they can also behave as satellites by parasitizing other males' calls. Males reared in an environment mimicking a population with many calling males were less likely to exhibit satellite behavior, invested more in reproductive tissues, and attained higher condition than males reared in a silent environment. These results contrast with other studies and demonstrate how the effects of juvenile social experience on adult male morphology, reproductive investment, and behavior may subsequently influence sexual selection and phenotypic evolution.

Polychlorinated Biphenyls, Dioxins, Furans, and Organochlorine Pesticides in Belted Kingfisher Eggs from the Upper Hudson River Basin, New York, USA

Environmental Toxicology and Chemistry / SETAC. Jan, 2010  |  Pubmed ID: 20821424

Nesting belted kingfishers (hereafter kingfishers, Ceryle alcyon) were studied on the Hudson River near Fort Edward south to New Baltimore (NY, USA) and three nearby river drainages in 2004. Concentrations of 28 organochlorine pesticides, 160 polychlorinated biphenyl (PCB) congeners, and 17 dioxin and furan (PCDD-F) congeners were quantified in kingfisher eggs. The pattern of organochlorine pesticides and PCDD-F congeners did not differ significantly between 14 eggs collected from individual nests on the Hudson River and five eggs similarly collected on three other nearby rivers. In contrast, the pattern of PCB congeners in eggs collected on the Hudson River differed significantly from the other rivers. The differences in patterns of PCB congeners were associated with a higher representation of lower-numbered congeners on the Hudson River than the other rivers. The higher prevalence of the lower-numbered congeners and lower prevalence of the higher-numbered congeners is consistent with Aroclor 1016 and 1242 being the source of the PCBs on the Hudson River. Concentrations in a sample egg collected at each nest were compared to nest survival and egg success (the proportion of eggs hatching in a clutch if at least one egg hatched) of the remaining eggs in the clutch. Models that predicted nest survival and egg success as functions of contaminant levels were poorly distinguished from models that presumed no such associations. Small sample sizes could have contributed to the inability to distinguish among contaminant and no toxicant models. However, we cannot rule out the possibility that contaminant concentrations on the Hudson River were not sufficiently high to demonstrate a relationship between contaminant concentrations and reproductive success in kingfishers.

Effects of Egg Order on Organic and Inorganic Element Concentrations and Egg Characteristics in Tree Swallows, Tachycineta Bicolor

Environmental Toxicology and Chemistry / SETAC. Apr, 2010  |  Pubmed ID: 20821521

The laying order of tree swallow eggs was identified from the Housatonic River, Berkshire County, Massachusetts, USA, and eggs were chemically analyzed individually to document possible effects of laying order on organic contaminant and inorganic element concentrations. Effects of laying order on other parameters such as egg weight, size, and lipid and moisture content also were assessed. Some effects of egg order on total polychlorinated biphenyls (PCBs) were detected, but the effect was not uniform across individual females or between years. In 2004, clutches with higher total PCBs tended to have concentrations decline across egg order, whereas clutches with lower concentrations of PCBs tended to increase across egg order. In contrast, in 2005, there was a tendency for concentrations to increase across egg order. Polychlorinated biphenyl concentrations were highly variable within and among clutches in both years. The directionality of egg order associations (i.e., slopes) for trace elements was element dependent, was positive for Mn and Zn, was negative for B, and had no slope for Cr. Whole egg weight increased across egg order. Percentage lipid was variable within a clutch, with no pattern common across all females. Percentage lipid was also correlated with organic contaminant concentration. In highly contaminated environments, higher lipid content could have the unanticipated corollary of having higher concentrations of lipophilic contaminants such as PCBs. To reduce the effect of high variation within a clutch when assessing contamination exposure, it is recommended that two eggs per clutch be collected and pooled for chemical analysis. We further recommend that, as long as the two eggs are randomly collected, the additional effort needed to identify and collect specific eggs is not warranted.

Helicobacter Pylori Induction of the Gastrin Promoter Through GC-rich DNA Elements

Helicobacter. Oct, 2010  |  Pubmed ID: 21083750

Helicobacter pylori (H. pylori) infection has been linked to the development of chronic gastritis, duodenal ulcer disease, and gastric cancer. Helicobacter pylori- infected patients and animal models develop hypergastrinemia, chronic gastritis, and gastric atrophy. Since gastrin is an important regulator of gastric acid secretion and cell growth, H. pylori regulation of this hormone has been implicated in its pathogenesis.

Awareness and Compliance with Recommended Running Shoe Guidelines Among U.S. Army Soldiers

Military Medicine. Nov, 2010  |  Pubmed ID: 21121493

The purpose of this study was to determine awareness and compliance with recommended running shoe selection, sizing, and replacement guidelines among U.S. Army soldiers. Soldiers (n = 524) attending training at Fort Sam Houston, Texas completed self-report questionnaires and a foot assessment, which included measurement of foot size and arch height index. Researchers examined each soldier's running shoes for type, wear pattern, and general condition. Thirty-five percent of the soldiers wore shoes that were inappropriately sized; 56.5% wore shoes that were inappropriate for their foot type. Thirty-five percent of the soldiers had excessively worn shoes and 63% did not know recommended shoe replacement guidelines. Further efforts may be necessary to ensure that soldiers are aware of and compliant with recommended running shoe selection, sizing, and replacement guidelines. Future research is needed to determine whether adherence to these guidelines has a favorable effect on reducing risk of overuse injury.

Exposure to Sexual Signals During Rearing Increases Immune Defence in Adult Field Crickets

Biology Letters. Apr, 2011  |  Pubmed ID: 20810430

Increased investment in immunity is expected to be beneficial under crowded conditions because of the greater risk of pathogen and parasite transmission, but the evolution of this facultative response relies on the ability to accurately assess social cues in the environment and adjust immune defences accordingly. Because of their highly conspicuous nature, long-range sexual signals are prime candidates to be used in evaluating the social conditions likely to be experienced upon adulthood in continuously breeding species; however, their role in mediating immune responses is unknown. We tested whether exposure to acoustic sexual signals in the field cricket Teleogryllus oceanicus affects immunity by manipulating male juvenile experience of acoustic signals, and measuring the effect on adult immunity. Adult males exposed to song during rearing showed stronger immune responses than males reared in silence: they were better able to encapsulate artificial nylon implants and showed higher levels of antimicrobial lysozyme-like activity in their haemolymph. Experience of sexual signals thus translates into increased immunity, which suggests that such signals may play a role in conveying information about population demography and shaping density-dependent responses in unintended receivers.

The Role of Sensory Organs and the Forebrain for the Development of the Craniofacial Shape As Revealed by Foxg1-cre-mediated MicroRNA Loss

Genesis (New York, N.Y. : 2000). Apr, 2011  |  Pubmed ID: 21225654

Cranial development is critically influenced by the relative growth of distinct elements. Previous studies have shown that the transcription factor Foxg1 is essential the for development of the telencephalon, olfactory epithelium, parts of the eye and the ear. Here we investigate the effects of a Foxg1-cre-mediated conditional deletion of Dicer1 and microRNA (miRNA) depletion on mouse embryos. We report the rapid and complete loss of the telencephalon and cerebellum as well as the severe reduction in the ears and loss of the anterior half of the eyes. These losses result in unexpectedly limited malformations of anterodorsal aspects of the skull. We investigated the progressive disappearance of these initially developing structures and found a specific miRNA of nervous tissue, miR-124, to disappear before reduction in growth of the specific neurosensory areas. Correlated with the absence of miR-124, these areas showed numerous apoptotic cells that stained positive for anticleaved caspase 3 and the phosphatidylserine stain PSVue® before the near or complete loss of those brain and sensory areas (forebrain, cerebellum, anterior retina, and ear). We conclude that Foxg1-cre-mediated conditional deletion of Dicer1 leads to the absence of functional miRNA followed by complete or nearly complete loss of neurons. Embryonic neurosensory development therefore depends critically on miRNA. Our data further suggest that loss of a given neuronal compartment can be triggered using early deletion of Dicer1 and thus provides a novel means to genetically remove specific neurosensory areas to investigate loss of their function on morphology (this study) or signal processing within the brain.

Targeting Apoptosis for Optical Imaging of Infection

Molecular Imaging and Biology : MIB : the Official Publication of the Academy of Molecular Imaging. May, 2011  |  Pubmed ID: 21538153

PURPOSE: Infection is ubiquitous and a major cause of morbidity and mortality. The most reliable method for localizing infection requires radiolabeling autologous white blood cells ex vivo. A compound that can be injected directly into a patient and can selectively image infectious foci will eliminate the drawbacks. The resolution of infection is associated with neutrophil apoptosis and necrosis presenting phosphatidylserine (PS) on the neutrophil outer leaflet. Targeting PS with intravenous administration of a PS-specific, near-infrared (NIR) fluorophore will permit localization of infectious foci by optical imaging. METHODS: Bacterial infection and sterile inflammation were induced in separate groups (n = 5) of mice. PS was targeted with a NIR fluorophore, PSVue(®)794 (2.7 pmol). Imaging was performed (ex = 730 nm, em = 830 nm) using Kodak Multispectral FX-Pro system. The contralateral normal thigh served as an individualized control. Confocal microscopy of normal and apoptotic neutrophils and bacteria confirmed PS specificity. RESULTS: Lesions, with a 10-s image acquisition, were unequivocally visible at 5 min post-injection. At 3 h post-injection, the lesion to background intensity ratios in the foci of infection (6.6 ± 0.2) were greater than those in inflammation (3.2 ± 0.5). Image fusions confirmed anatomical locations of the lesions. Confocal microscopy determined the fluorophore specificity for PS. CONCLUSIONS: Targeting PS presented on the outer leaflet of apoptotic or necrotic neutrophils as well as gram-positive microorganism with PS-specific NIR fluorophore provides a sensitive means of imaging infection. Literature indicates that NIR fluorophores can be detected 7-14 cm deep in tissue. This observation together with the excellent results and the continued development of versatile imaging devices could make optical imaging a simple, specific, and rapid modality for imaging infection.

Synthesis and Preliminary Evaluation of Radiolabeled Bis(zinc(II)-dipicolylamine) Coordination Complexes As Cell Death Imaging Agents

Bioorganic & Medicinal Chemistry. Jun, 2011  |  Pubmed ID: 21570306

The aim of this study was the development of (⁹⁹m)Tc labeled bis(zinc(II)-dipicolylamine) (Zn²⁺-DPA) coordination complexes, and the in vivo evaluation of their usefulness as radiotracers for the detection of cell death. DPA ligand 1 was labeled with (⁹⁹m)Tc via the (⁹⁹m)Tc-tricarbonyl core ([(⁹⁹m)Tc(CO)₃-1]³⁺) or via HYNIC ((⁹⁹m)Tc-HYNIC-1) in good radiochemical yields. Highest in vitro stabilities were demonstrated for [(⁹⁹m)Tc(CO)₃-1]³⁺. A mouse model of hepatic apoptosis (anti-Fas mAb) was used to demonstrate binding to apoptotic cells. (⁹⁹m)Tc-HYNIC-1 showed the best targeting of apoptotic hepatic tissue with a 2.2 times higher liver uptake in anti-Fas treated mice as compared to healthy animals. A rat model of ischemia-reperfusion injury was used to further explore the ability of the (⁹⁹m)Tc-labeled Zn²⁺-DPA coordination complexes to target cell death. Selective accumulation could be detected for both tracers in the area at risk, correlating with histological proof of cell death. Area at risk to normal tissue uptake ratios were 3.82 for [(⁹⁹m)Tc(CO)₃-1]³⁺ and 5.45 for (⁹⁹m)Tc-HYNIC-1.

Erratum To: Targeting Apoptosis for Optical Imaging of Infection

Molecular Imaging and Biology : MIB : the Official Publication of the Academy of Molecular Imaging. May, 2011  |  Pubmed ID: 21607735

Effects of Injected Methylmercury on the Hatching of Common Loon (Gavia Immer) Eggs

Ecotoxicology (London, England). Oct, 2011  |  Pubmed ID: 21789674

To determine the level of in ovo methylmercury (MeHg) exposure that results in detrimental effects on fitness and survival of loon embryos and hatched chicks, we conducted a field study in which we injected eggs with various doses of MeHg on day 4 of incubation. Eggs were collected following about 23 days of natural incubation and artificially incubated to observe hatching. Reduced embryo survival was evident in eggs injected at a rate of ≥1.3 μg Hg/g wet-mass. When maternally deposited Hg and injected Hg were considered together, the median lethal concentration of Hg (LC(50)) was estimated to be 1.78 μg Hg/g wet-mass. Organ mass patterns from eggs of chicks injected at a rate of 2.9 μg Hg/g differed from that of controls and chicks from the 0.5 μg Hg/g treatment, largely related to a negative relation between yolk sac mass and egg mercury concentration. Chicks from eggs in the 2.9 μg Hg/g treatment were also less responsive to a frightening stimulus than controls and chicks from the 0.5 μg Hg/g treatment. We also found that the length of incubation period increased with increasing egg mercury concentration. Tissue Hg concentrations were strongly associated (r(2) ≥ 0.80) with egg Hg concentration.

Detection of Myocardial Ischemia-Reperfusion Injury Using a Fluorescent Near-Infrared Zinc(ii)-Dipicolylamine Probe and (99m)Tc Glucarate

Molecular Imaging. Sep, 2011  |  Pubmed ID: 21961458

A fluorescent zinc 2,2'-dipicolylamine coordination complex PSVue(®)794 (probe 1) is known to selectively bind to phosphatidylserine exposed on the surface of apoptotic and necrotic cells. In this study, we investigated the cell death targeting properties of probe 1 in myocardial ischemia-reperfusion injury. A rat heart model of ischemia-reperfusion was used. Probe 1, control dye, or (99m)Tc glucarate was intravenously injected in rats subjected to 30-minute and 5-minute myocardial ischemia followed by 2-hour reperfusion. At 90 minutes or 20 hours postinjection, myocardial uptake was evaluated ex vivo by fluorescence imaging and autoradiography. Hematoxylin-eosin and cleaved caspase-3 staining was performed on myocardial sections to demonstrate the presence of ischemia-reperfusion injury and apoptosis. Selective accumulation of probe 1 could be detected in the area at risk up to 20 hours postinjection. Similar topography and extent of uptake of probe 1 and (99m)Tc glucarate were observed at 90 minutes postinjection. Histologic analysis demonstrated the presence of necrosis, but only a few apoptotic cells could be detected. Probe 1 selectively accumulates in myocardial ischemia-reperfusion injury and is a promising cell death imaging tool.

Restorative Proctocolectomy Without Diverting Ileostomy in Children with Ulcerative Colitis

Journal of Pediatric Surgery. Jan, 2012  |  Pubmed ID: 22244418

The safety of performing a restorative proctocolectomy (RP) and J-pouch ileoanal anastomosis (IPAA) without diverting ileostomy for children with ulcerative colitis (UC) is a subject of extensive debate. Our goal was to examine pediatric outcomes of RP and IPAA without ileostomy.

Radiolabeled Zn-DPA As a Potential Infection Imaging Agent

Nuclear Medicine and Biology. Feb, 2012  |  Pubmed ID: 22321532

INTRODUCTION: A zinc-dipicolylamine analog (Zn-DPA) conjugated with a fluorophore (PSVue®794) has been shown to image bacterial infections in mice. However, radiolabeled Zn-DPA has not previously been considered for nuclear imaging of infection. METHODS: Both (111)In-labeled DOTA-biotin and Zn-DPA-biotin were combined using streptavidin (SA) as a noncovalent linker. Mice injected intramuscularly with Streptococcus pyogenes (infection model) or with lipopolysaccharide (LPS) (inflammation model) were coinjected intravenously with 6 μg of DPA as PSVue794 and as (111)In-DOTA-biotin/SA/biotin-Zn-DPA. Periodic fluorescent and SPECT (single photon emission computed tomography)/CT (computed tomography) images were acquired, and biodistributions were obtained at 22 h. RESULTS: Histological examination confirmed the validity of both the infection and inflammation animal models. Both the whole-body optical and nuclear images showed obvious accumulations in the target thigh in both models at all time points. At 22 h, the average target thigh accumulation of (111)In was 1.66%ID/g (S.D. 0.15) in the infection mice compared to 0.58%ID/g (S.D. 0.07) in the inflammation mice (P<.01), and the (111)In target/normal thigh ratio was 2.8 fold higher in the infection animals compared to the inflammation animals. CONCLUSIONS: These preliminary results show that Zn-DPA within streptavidin targets S. pyogenes-infected mice similarly to its free fluorescent analogue. The significantly higher accumulation in the live bacterial infection thigh compared to that of the LPS-induced inflammation thigh suggests that Zn-DPA may be a promising imaging agent to distinguish between bacterial infections and sterile inflammations.

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